Sodium metal batteries suffer from severe capacity decay due to the continuous side-reactions between sodium metal anode and conventional carbonate electrolyte using porous glass fiber (GF) membranes as the separator, especially at elevated temperature. Moreover, sodium dendrites preferentially propagate through the low-modulus pores and cause severe safety issues. Here a compact gel polymer electrolyte (GF-GPE) with high ionic conductivity is developed by tightly immobilizing liquid electrolyte in polymer matrix embedded in GF membranes. The extensive interaction between the liquid electrolyte and polymer matrix promotes the formation of a stable Na/GF-GPE interface to effectively reduce the side reactions at both room and elevated temperature. The GF-GPE could regulate the depth concentration profile of NaF, a key solid electrolyte interphase (SEI) component, to deter sodium dendrites formation and side reactions. As a result, the Na₃V₂(PO₄)₃/GF-GPE/Na cell presents outstanding cycling stability. Its capacity retention after 2000 cycles at 1C under room temperature is as high as 95% and that after 500 cycles at 60 °C reaches 84%. This study successfully develops a robust and scalable approach by using a compact gel polymer electrolyte to achieve stable sodium metal anodes at room and elevated temperature.

由于钠金属阳极与使用多孔玻璃纤维（GF）膜作为隔板的常规碳酸盐电解质之间的连续副反应，特别是在高温下，钠金属电池遭受严重的容量衰减。此外，钠树枝状晶体优先通过低模量孔传播，并引起严重的安全问题。在此，通过将液态电解质紧紧固定在嵌入GF膜的聚合物基质中，开发出一种具有高离子电导率的紧凑型凝胶聚合物电解质（GF-GPE）。液体电解质和聚合物基质之间的广泛相互作用促进了稳定的Na / GF-GPE界面的形成，从而有效地降低了室温和高温下的副反应。GF-GPE可以调节NaF的深度浓度分布，关键的固体电解质中间相（SEI）成分，可以阻止钠树枝状晶体的形成和副反应。结果，Na₃ V ₂（PO ₄）₃ / GF-GPE / Na电池具有出色的循环稳定性。在室温下于1C下进行2000次循环后，其容量保持率高达95％，在60°C下经过500次循环后，其容量保持率达到84％。这项研究通过使用紧凑的凝胶聚合物电解质成功地开发了一种健壮且可扩展的方法，以在室温和高温下实现稳定的钠金属阳极。